#define _CRT_SECURE_NO_WARNINGS 1
class Solution {
public:
    int dx[4] = { 0,0,1,-1 };
    int dy[4] = { 1,-1,0,0 };
    int numEnclaves(vector<vector<int>>& grid) {
        int m = grid.size(), n = grid[0].size();
        vector<vector<bool>>vis(m, vector<bool>(n));
        queue<pair<int, int>>q;
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
            {
                if ((i == 0 || i == m - 1 || j == 0 || j == n - 1) && grid[i][j] == 1)
                {

                    q.push({ i,j });
                    vis[i][j] = true;
                }
            }
        }
        int ret = 0;
        while (q.size())
        {
            auto [a, b] = q.front();
            q.pop();
            for (int k = 0; k < 4; k++)
            {
                int x = a + dx[k], y = b + dy[k];
                if (x >= 0 && x < m && y >= 0 && y < n && !vis[x][y] && grid[x][y] == 1)
                {
                    vis[x][y] = true;
                    q.push({ x,y });
                }
            }
        }
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
            {
                if (grid[i][j] == 1 && !vis[i][j]) ret++;
            }
        }
        return ret;
    }
};